Soon after that, the thread was picked up in Egypt by a TV host every bit as inflammatory and opportunistic as Jones: Sheik Khaled Abdallah of the Islamist satellite-TV station al-Nas. Supported by unknown backers, the channel traffics in demagoguery and hatemongering. Abdallah is its star. In previous broadcasts, he has called the revolutionaries of the Arab Spring “worthless kids” and condemned newspapers that don’t support his views. But he reserves his harshest criticism for the country’s Coptic Christians, who make up about a tenth of the population.

For Abdallah, the fact that a Copt was promoting an anti-Muhammad film endorsed by the Koran-burning pastor was too much. On his Sept. 8 show, he broadcast some of the clips, now dubbed in Arabic. In one scene that was aired, “Muhammad” declares a donkey the “first Muslim animal” and asks the creature if it likes the ladies. Abdallah’s show, complete with the offensive video, was also posted on YouTube, and it has attracted over 300,000 views.

Abdallah’s show was a dog whistle to the Salafists, a fundamentalist Islamic movement that makes up the second largest faction in the Egyptian parliament. For months, organized Salafist groups had been protesting in small numbers in front of the U.S. embassy in Cairo, calling for the release of Omar Abdel Rahman, the blind sheik currently in a North Carolina prison, convicted for plotting a series of bombings and assassinations in the 1990s. They were joined on Sept. 11 by prominent leaders like Nader Bakar of the Salafist Nour Party and Mohammed al-Zawahiri, brother of Ayman al-Zawahiri, Osama bin Laden’s longtime deputy and now head of al-Qaeda.

The leaders had left by the time the mob attacked the embassy and took down the U.S. flag, while Egyptian security forces, hopelessly outnumbered, mostly just watched. The crowd eventually dispersed. Afterward, some Salafist leaders said the flag was snatched by members of a soccer-hooligan group known as the Ahli Ultras.

Not far from Egypt’s western border, in the Libyan city of Benghazi, on the anniversary of the 2001 attacks at the World Trade Center, the Muhammad movie had provoked another mob of several hundred mostly Salafist protesters to gather at the U.S. consulate. Many witnesses have since fingered a group known as Ansar al-Shari‘a for organizing the protests; the group denies it.

Ambassador Stevens, visiting from Tripoli, was an unlikely target. He had worked closely with the leaders of the uprising against Muammar Gaddafi and was well liked by most Libyans. But some reports now suggest that lurking amid the mob was a more malevolent force: members of the local chapter of al-Qaeda.

Only the previous day, Ayman al-Zawahiri had issued a new videotaped statement from his hideout, confirming the death of his Libyan deputy Abu Yahya al-Libi in a June U.S. drone strike and calling for him to be avenged. Reports from Benghazi say armed jihadists infiltrated the protesting crowds. An al-Qaeda-affiliated group known as the Imprisoned Omar Abdul Rahman Brigades is suspected to have carried out the attack. The White House was still scrambling a day after the attack to piece together what happened and whether it could have been prevented. A senior Administration official said the Benghazi attack was “complex” and “well organized” but would not comment on reports that it was planned in advance by militants using the protest as a diversion.